Performance issue in high-unit missions

[TheHoff]

Greetings

I've been fiddling with an issue I've had for a while, trying to understand what cause this. So far I've deduced that whenever I load a mission with a high number of preloaded ground or air units my FPS suffers. Examples of missions are those generated by Liberation dynamic campaign or the excellent Syria Framework.

The thing is if I use the Nvidia overlay my GPU is fluctuating from 50%-99% as well as my CPU going from 10%-40%. I get the feeling the GPU stops processing while waiting for the CPU to do something. I would understand the FPS issue if all processors were at 99% but they aren't. If I run a "normal" mission like a official campaign I get 10-20% CPU and a constant 99% GPU and FPS is just fine by my standards. I've been trying to disable different addons to DCS like Tacview but that doesn't improve things.

I don't have a monster PC per se but still, AMD Ryzen5 3600XT, Asus 3060ti, 32gb RAM, M2 SSD. Again, since the processors aren't even running at their potential it seems to me it's "something else".

 

Please help me understand this. 

 

Regards

Fredrik

[speed-of-heat]

Dcs is really only able to use a couple of cores at the same time so with your twelve threads that cpu performance is like about right… the fluctuation is concerning and you should look for background tasks that are causing the disruption. And ensure you have disabled tacview…

[Boosterdog]

Triggered actions and AI route finding can be problematic as they cause spikes in the CPU use. As Speedofheat has already said, DCS is core limited. Even "official" missions can suffer from this. The MI24 distaster relief mission is the worst culprit i know right now. Its not an especially heavy missiion but stutters along as units go active, route find and trigger.  It been pointed out to me that is a graphically heavy mission, but even now Im able to run it at over 120 fps on meduim settings, when something triggers, everything stops. 

Hopefully the migration to multicore planned for DCS will improve matters but this is currently nothing more than vapour with no roadmap and no current indication of implmentation. 

 

[TheHoff]

Comforting answers, or at least I will look into my mission start behavior a bit. Since I'm usually time constrained when I have an opportunity for DCS I mostly aim to get fighting ASAP (I know I know, mission planning etc is everything) but if I have an hour tops I want to maximize my flying. This might lead me to get into the air before all units are calculated by DCS as you guys describe.

Tacview and such are already disabled and since these problems only occur during very detailed missions I'm more inclined toward Boosterdog's answer.

 

/Fredrik

[speed-of-heat]

I don’t think it matters particularly “how long you wait to go” it’s just likely to be the sheer volume of ai

[TheHoff]

I'm bumping this just because after spending most of my DCS time in campaigns I last week had another round at the Syria Framework mission with great anticipation at some nice flying and later tried to run a few Caucasus missions created through Liberation. Neither worked at all and I got around 10 FPS for both missions long after I loaded into them and at both occurrences my CPU was around 20% and my GPU between 40%-70%. On a "regular" mission like any of the paid campaigns or free ones the GPU quickly goes to 99% and pretty much stays there. I totally fail to understand why DCS doesn't utilize the whole GPU for some missions! If the CPU were also at or near max I would understand the bottleneck but it's almost like DCS isn't even trying.

Nothing has changed on my side, still the same AMD Ryzen5 3600XT, Asus 3060ti, 32gb RAM, M2 SSD and I'm keeping current with the beta release track.

Edited October 1, 2022 by TheHoff

[speed-of-heat]

The CPU% is most likely a percentage the total CPU.  DCS will only utilise 2-3 cores, because of the way it is coded. There are a boat load of threads on this, and Ed is aware , and is in the process of refactoring the code to make better use of modern CPU’s, but, don’t hold your breath.

if you look at individual cores within the cpu you will see that some are 100% utilised.

The reason your GPU is under-utilised is you are CPU bottlenecked by the vast numbers of scripts and AI. I would take the template and remove the units you don’t need for the mission…